Why do my vertices fade the further I zoom in?
The reason why the actual wire is partially hidden is because the actual geometry is affected by the Subdivision Surface Modifier and you see a modified version of the mesh, even in Edit Mode.
https://docs.blender.org/manual/en/latest/modeling/modifiers/generate/subdivision_surface.html

I'd suggest go to the Modifier Panel and enable 'On Cage' option of the Subdivision Surface Modifier by clicking the little triangle icon

or just disable the modifier temporary in order to affect how the mesh is visualized in Edit Mode.


The reason why zoom in/out affects those &quot;fading&quot; vertices is because blender is displaying partially wire inside of a mesh to improve viewport experience for vertices that would be quickly hidden in sharp angle view. This &quot;inside&quot; view is constant for viewport, but actual distances of vertices in viewport are changing.